S3 snapshot repositories not working after upgrade from 1.7 to 2.3

We have several snapshot repositories, created on a 1.7 cluster, that have their type property set to "S3". We also have several with type "s3". It seems that for a time elasticsearch accepted both "S3" and "s3" as a type, but now only accepts "s3".

When we upgraded to 2.3, on startup we get errors like the following for each of the "S3" repos:

[2016-07-23 05:19:42,914][WARN ][repositories             ] [snip] failed to create repository [S3][snip]
java.lang.IllegalArgumentException: Unknown [repository] type [S3]
        at org.elasticsearch.common.util.ExtensionPoint$SelectedType.bindType(ExtensionPoint.java:146)
        at org.elasticsearch.repositories.RepositoryTypesRegistry.bindType(RepositoryTypesRegistry.java:49)
        at org.elasticsearch.repositories.RepositoryModule.configure(RepositoryModule.java:58)
        at org.elasticsearch.common.inject.AbstractModule.configure(AbstractModule.java:60)
        at org.elasticsearch.common.inject.spi.Elements$RecordingBinder.install(Elements.java:233)
        at org.elasticsearch.common.inject.spi.Elements.getElements(Elements.java:105)
        at org.elasticsearch.common.inject.InjectorShell$Builder.build(InjectorShell.java:143)
        at org.elasticsearch.common.inject.InjectorBuilder.build(InjectorBuilder.java:99)
        at org.elasticsearch.common.inject.InjectorImpl.createChildInjector(InjectorImpl.java:157)
        at org.elasticsearch.common.inject.ModulesBuilder.createChildInjector(ModulesBuilder.java:55)
        at org.elasticsearch.repositories.RepositoriesService.createRepositoryHolder(RepositoriesService.java:404)
        at org.elasticsearch.repositories.RepositoriesService.clusterChanged(RepositoriesService.java:299)
        at org.elasticsearch.cluster.service.InternalClusterService.runTasksForExecutor(InternalClusterService.java:610)
        at org.elasticsearch.cluster.service.InternalClusterService$UpdateTask.run(InternalClusterService.java:772)
        at org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.runAndClean(PrioritizedEsThreadPoolExecutor.java:231)
        at org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.run(PrioritizedEsThreadPoolExecutor.java:194)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at java.lang.Thread.run(Thread.java:745)

Is it possible to change the type property on a repo?

Thank you for reporting.

I just opened this https://github.com/elastic/elasticsearch/issues/19570